Mass spectra of the compounds were obtained using Finnigan MAT 312 machine. The purity of the synthesized compounds was checked by precoated TLC plate (E. Merck Kieselgel 60 F254). Method (a): A mixture

of 2-aminobenzamide (1.0 g, 7.4 mmol) and phthalic anhydride (isobenzofuran-1,3-dione) (1.09 g, 7.4 mmol) was powdered and introduced into a beaker. 5 mL of ethanol was added to form a homogeneous solution, covered with a watch glass and then irradiated in a microwave oven at 400 W, at 30 s intervals, for a total of 10 min. The crude product was purified using flash chromatography [on silica gel; elution selleckchem with petroleum ether–chloroform (1:1)] to afford ethyl 2-(4-oxo-3,4-dihydroquinazolin-2-yl)benzoate 5 as a yellow solid (1.50 g, 69%), m.p. 220–222 °C; υmax/cm−1 (KBr) 3170 (NH), 1730 (C O of ester), 1656 (C O of amide), 1610 (C N), 1299, 1263, 1132 (C–O); δH (200 MHz, CDCl3) 1.00 (3H, t, CH3),

4.10 (2H, q, COOCH2), 7.50–7.82 (6H, m, ArH), 8.10 (1H, d, ArH), 8.20 (1H, d, ArH), 12.08 (br, 1H, s, NH); δC (50 MHz, CDCl3) 14.1 (CH3), 61.6 (OCH2), 120.9 (Cq, Ar), 126.6 (CH, Ar), 127.1 (CH, Ar), 127.9 (CH, Ar), 130.1 (CH, Ar), 130.7 (CH, Ar), 130.8 (CH, Ar), 131.0 (Cq, Ar), 132.3 (CH, Ar), 135.0 (Cq, Ar), 135.1 (CH, Ar), 149.4 (Cq, Ar), 153.9 (Cq, Ar), 163.8 (C O), 166.8 (C O); m/z (rel. %) 295 [(M + H)+, 100], 249 (98), 233 (59). Method (b): A mixture of 2-aminobenzamide (1.0 g, 7.4 mmol), phthalic anhydride (1.09 g, 7.4 mmol), silica gel (230–240 mesh, Merck, 5 g) and 5 drops of acetic acid was powdered and introduced into a beaker, covered with a glass and irradiated in a microwave oven at 700 W power for 2 min. This was followed by another irradiation BKM120 solubility dmso tuclazepam at 400 W for 5 min. Purification of the crude using flash chromatography [on silica gel; elution with petroleum

ether–chloroform (1:1)] afforded compound 5 in (1.35 g, 62%). A mixture of 2-aminobenzamide (2.72 g, 20.0 mmol) and succinic anhydride (dihydrofuran-2,5-dione) (2.00 g, 20.0 mmol) was powdered and introduced into a beaker, covered with a watch glass and irradiated in a microwave oven at 400 W for a total of 15 min (at 30 s intervals) to give a yellow viscous liquid. The liquid gave a positive (NaHCO3) test for carboxylic acid functional group. After 24 h, during which there was no crystallization from the viscous liquid, 7 drops of acetic acid and 15 mL of ethanol were added to the reaction mixture and was further irradiated for 15 min. The mixture was concentrated in vacuo and purified using flash chromatography [on silica gel; elution with chloroform–ethyl acetate (1:1)] to afford 3-(3,4-dihydro-4-oxoquinazolin-2-yl)propanoic acid as a white solid (1.24 g, 85%), m.p. 201–203 °C; υmax/cm−1 (Nujol): 3383 (NH), 1704 (C O), 1663 (C O of amide), 1615 (C N); δH (200 MHz, DMSO-d6) 2.70 (2H, t), 2.90 (2H, t), 7.00–8.40 (4H, m, ArH), 11.70 (NH), 12.30 (br, 1H, s, OH); δC (50 MHz, DMSO-d6) 29.8 (CH2), 30.5 (CH2), 121.